1. Field of the Invention
The present invention generally relates to a support assembly for supporting thereon an electric appliance such as, for example, a computer display unit or an audio equipment and, in particular but not exclusively, to a rotary stand for the electric appliance that is effective to improve functionality of the electric appliance by allowing the latter to be adjustable in orientation depending on the site in which the electric appliance is placed.
2. Description of the Related Art
The conventional rotary stand is known to include a pedestal formed with a spherically concave portion, and an electric appliance such as, for example, a computer display unit or an audio equipment is mounted thereon through a mounting plate having a concave portion complementary in shape to the shape of the spherically concave portion. The pedestal has a center portion formed integrally with a hollow cylindrical boss that is loosely inserted through an elongated opening defined in a center portion of a mounting plate on which the electric appliance is mounted, with a clamp plate biased by a screwed spring element towards the mounting plate so that the electric appliance on the mounting plate can be tilted up and down and/or swung leftwards and rightwards.
However, with the conventional rotary stand of the structure discussed above, when the electric appliance mounted on the mounting plate of the rotary stand is tilted or swung, the clamp plate then biased by the spring element rotate together with the mounting plate. Accordingly, the cylindrical boss integral with the pedestal, which extends through a center hole in the clamp plate to hold the clamp plate, has one end face susceptible to frictional wear, or obnoxious sounds tend to be generated between the spring element and the screw, resulting in the possibility that the spring comes to rotate with increase in frequency of use to eventually loosen the screw.
The screw engaged in the cylindrical boss integral with the pedestal is normally biased by the spring element in a direction counter to the direction in which the screw is fastened into the cylindrical boss. Accordingly, repeated tilt and/or swing of the rotary stand or the use thereof in an environment rich of oil would result in cracking in the cylindrical boss or, if not at all, a detrimental fracture of the cylindrical boss.
The present invention has been developed to overcome the above-described disadvantages.
It is accordingly an objective of the present invention to provide a highly reliable, robust and simplified rotary stand wherein the functionality thereof is increased by allowing the display unit or the audio equipment to be oriented in any direction as desired, and wherein both the possibility of the obnoxious sounds generated between the spring used to bias the clamp plate and the screw and the possible loosening of the screw used to press the spring which would otherwise take place as the frequency of use increases are substantially eliminated to thereby avoid any possible cracking in or fracture of the boss integral with the pedestal.
In accomplishing the above and other objectives, the present invention provides a rotary stand for the support thereon of a display unit or an audio equipment, which includes a pedestal having a spherically concave portion and a regulating projection formed in the spherically concave portion, a mounting plate having a bearing portion of a shape corresponding to the spherically concave portion and adapted to support thereon the display unit or the audio equipment, and a clamp plate having a shape similar to the bearing portion of the mounting plate for clamping the mounting plate between it and the pedestal while allowing the mounting plate to undergo a swinging motion leftwardly and rightwardly and also a tilting motion up and down. The bearing portion of the mounting plate has a slot defined therein, and the angle of any one of swing and tilt of the mounting plate is regulated by causing side edges of the regulating projection to engage corresponding inner side edges of the slot.
According to the present invention, in view of the fact that the display unit or the audio equipment can be oriented in any desired direction within a predetermined angle of tilt and/or within a predetermined angle of swing, the functionality of the device can advantageously be increased.
In one preferred embodiment, the slot referred to above has a pair of parallel long side edges and, when the side edges of the regulating projection are brought into engagement with the long side edges of the slot, the angle of swing in a leftward or rightward direction is limited, whereas when the side edges of the regulating projection are brought into engagement with inner edges of the slot other than the long side edges, the angle of tilt in an upward or downward direction is limited. This arrangement enables the functionality of the device to be increased with a simplified construction.
Preferably, the regulating projection has approximately right-angled corners one on each end of a major axis thereof and also has side edges one on each end of a minor axis thereof. In this case, each of the side edges is curved to represent a generally arcuated shape, and the regulating projection has a width as measured in a direction along the minor axis thereof that is approximately equal to a width of the slot as defined between the long side edges of the slot. This arrangement also enables the functionality of the device to be increased with a simplified construction.
In another preferred embodiment of the present invention, the spherically concave portion of the pedestal is formed with a rectangular projection and the clamp plate is formed with a generally rectangular opening defined therein. Opposite edge portions of the clamp plate that define opposite sides of the opening are bent downwardly to engage the rectangular projection to thereby allow the clamp plate to be retained relative to the pedestal. According to this embodiment, no members other than the mounting plate rotate even when the device is tilted and/or swung and, therefore, the highly reliable and robust rotary stand can be obtained in which the possibility is eliminated in which cracking or fracture may occur in the boss integral with the pedestal that is formed integrally with the regulating projection and the rectangular projection.
In a further preferred embodiment of the present invention, a spring having a lower end fixed to the pedestal may be provided for biasing the clamp plate towards the bearing portion of the mounting plate. This spring does not rotate relative to the pedestal and, therefore, there is no possibility of obnoxious sounds being otherwise generated between the spring and the screw. Also, even if the frequency of use of the rotary stand increases, there is no possibility of the spring being loosened.
The regulating projection and the rectangular projection may preferably have a common hole defined therein for passage of a screw therethrough with a free end thereof fastened by a nut to thereby connect the mounting plate, the clamp plate and the spring together with the pedestal. This arrangement is effective to avoid the possibility of cracking or fracture taking place in the boss even when the rotary stand is repeatedly swung and/or tilted and is used in an environment rich of oil.